20101901 has 4 divisors (see below), whose sum is σ = 20795100. Its totient is φ = 19408704.

The previous prime is 20101883. The next prime is 20101927. The reversal of 20101901 is 10910102.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 15217801 + 4884100 = 3901^2 + 2210^2 .

It is a cyclic number.

It is not a de Polignac number, because 20101901 - 2¹⁰ = 20100877 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20101951) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 346556 + ... + 346613.

It is an arithmetic number, because the mean of its divisors is an integer number (5198775).

Almost surely, 2^20101901 is an apocalyptic number.

It is an amenable number.

20101901 is a deficient number, since it is larger than the sum of its proper divisors (693199).

20101901 is an equidigital number, since it uses as much as digits as its factorization.

20101901 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 693198.

The product of its (nonzero) digits is 18, while the sum is 14.

The square root of 20101901 is about 4483.5143581793. The cubic root of 20101901 is about 271.9019840395.

The spelling of 20101901 in words is "twenty million, one hundred one thousand, nine hundred one".